1. Field of the Invention
This invention relates to a solar control device, and in particular to an apparatus for maximizing solar daylight, solar heat gain and heat retention in a structure during winter, and for providing ventilation and diffuse daylighting during the summer.
2. Description of the Prior Art
In the past, when non-renewable energy sources were relatively inexpensive, buildings used north facing skylights to provide the best natural lighting and also to provide apertures for ventilation. In recent years, with the advent of energy shortages, skylights are being oriented to face south and take advantage of the available solar energy. However, in order to provide a net heat gain in winter such skylights must be insulated at night. In order to accomplish night time insulation the prior art discloses the use of thermal blankets on rollers, rigid panels on hinges, beads blown in to the space between panes of glass, etc. U.S. Pat. No. 3,884,414 issued to Stephen Baer describes a relevant technique employing pivoted panels. Such solar control components primarily address one aspect of the total problem, namely, night time thermal insulation. In general they do not provide ventilation or daylighting during the non-heating season because they generally should be closed to prevent excessive heat gain. One interesting approach is described as a "Sun Scoop" and disclosed at the Sixth National Passive Solar Conference. Page 502 of those materials describes the "Sun Scoop" which was taken from a disclosure entitled "Road Map to the Stars: Teaching an Integrated Approach to Energy Conserving Design" by Joel E. Lakin and Marietta S. Millet, Department of Architecture, JO-20, University of Washington, Seattle, Wash. 98105. That particular device employed a rotating concave shutter that was concerned more with non-direct lighting than with direct lighting. A significant amount of energy loss is experienced if the natural direct light of the sun is not used to its fullest advantages.